I bought a pair of these Nalgene bottles 15 years ago and have used them happily every weekend since. The plastic loops that hold the caps to the bottle (to prevent loss) are finally developing cracks after 15 years, so I purchased a new pair of bottles. The new bottles are almost identical to the old -- except that the plastic is not quite as thick and the bottles not as rigid as 15 years ago. Will these last as long? We'll see.